Support python wheel build (#787)

## Support Python wheel build

This PR modernizes the Python packaging for MSCCL++ by defining
dependencies and optional extras in `pyproject.toml`, enabling proper
wheel builds with `pip install ".[cuda12]"`.

### Changes

**`pyproject.toml`**
- Add `dependencies` (numpy, blake3, pybind11, sortedcontainers)
- Add `optional-dependencies` for platform-specific CuPy (`cuda11`,
`cuda12`, `cuda13`, `rocm6`), `benchmark`, and `test` extras
- Bump minimum Python version from 3.8 to 3.10

**`test/deploy/setup.sh`**
- Use `pip install ".[<platform>,benchmark,test]"` instead of separate
`pip install -r requirements_*.txt` + `pip install .` steps
- Add missing CUDA 13 case

**`docs/quickstart.md`**
- Update install instructions to use extras (e.g., `pip install
".[cuda12]"`)
- Document all available extras and clarify that `rocm6` builds CuPy
from source
- Update Python version references to 3.10

**`python/csrc/CMakeLists.txt`**, **`python/test/CMakeLists.txt`**
- Update `find_package(Python)` from 3.8 to 3.10

### Notes
- The `requirements_*.txt` files are kept for Docker base image builds
where only dependencies (not the project itself) should be installed.
- CuPy is intentionally not in base dependencies — users must specify a
platform extra to get the correct pre-built wheel (or source build for
ROCm).

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

python/csrc/CMakeLists.txt

@@ -1,7 +1,7 @@
 # Copyright (c) Microsoft Corporation.
 # Licensed under the MIT license.
 
-find_package(Python 3.8 COMPONENTS Interpreter Development.Module REQUIRED)
+find_package(Python 3.10 COMPONENTS Interpreter Development.Module REQUIRED)
 include(FetchContent)
 FetchContent_Declare(nanobind GIT_REPOSITORY https://github.com/wjakob/nanobind.git GIT_TAG v1.9.2)
 FetchContent_MakeAvailable(nanobind)

python/mscclpp/_core/compiler.py

@@ -192,6 +192,9 @@ class NativeCodeCompiler:
     """
 
     def __init__(self):
+        self._initialized = False
+
+    def _do_init(self):
         self._is_hip = cp.cuda.runtime.is_hip
         self._device_arch = get_device_arch()
         self._compiler = self._get_compiler()
@@ -226,6 +229,7 @@ class NativeCodeCompiler:
         ]
         self._cache_dir = Path(env().cache_dir) / "native"
         self._cache_dir.mkdir(parents=True, exist_ok=True)
+        self._initialized = True
 
     def _get_compiler(self) -> str:
         """Get the path to the appropriate compiler.
@@ -246,6 +250,8 @@ class NativeCodeCompiler:
         Returns:
             str: The GPU architecture string (e.g., "sm_90" for NVIDIA or "gfx90a" for AMD).
         """
+        if not self._initialized:
+            self._do_init()
         return self._device_arch
 
     def __call__(self, name: str, file: str, **kwds):
@@ -290,6 +296,8 @@ class NativeCodeCompiler:
             >>> # Use the module to create an algorithm
             >>> algo = module.create_allreduce_algorithm(comm, buffer, size)
         """
+        if not self._initialized:
+            self._do_init()
         if not os.path.isfile(file):
             raise FileNotFoundError(f"The specified source file does not exist: {file}")
 

python/requirements_cuda11.txt

@@ -5,6 +5,6 @@ netifaces
 pytest
 numpy
 matplotlib
-sortedcontainers @ git+https://github.com/grantjenks/python-sortedcontainers.git@3ac358631f58c1347f1d6d2d92784117db0f38ed
+sortedcontainers
 blake3
 pybind11

python/requirements_cuda12.txt

@@ -5,6 +5,6 @@ netifaces
 pytest
 numpy
 matplotlib
-sortedcontainers @ git+https://github.com/grantjenks/python-sortedcontainers.git@3ac358631f58c1347f1d6d2d92784117db0f38ed
+sortedcontainers
 blake3
 pybind11

python/requirements_cuda13.txt

@@ -5,6 +5,6 @@ netifaces
 pytest
 numpy
 matplotlib
-sortedcontainers @ git+https://github.com/grantjenks/python-sortedcontainers.git@3ac358631f58c1347f1d6d2d92784117db0f38ed
+sortedcontainers
 blake3
 pybind11

python/requirements_rocm6.txt

@@ -5,6 +5,6 @@ netifaces
 pytest
 numpy
 matplotlib
-sortedcontainers @ git+https://github.com/grantjenks/python-sortedcontainers.git@3ac358631f58c1347f1d6d2d92784117db0f38ed
+sortedcontainers
 blake3
 pybind11

python/test/CMakeLists.txt

@@ -1,7 +1,7 @@
 # Copyright (c) Microsoft Corporation.
 # Licensed under the MIT license.
 
-find_package(Python 3.8 COMPONENTS Interpreter Development.Module REQUIRED)
+find_package(Python 3.10 COMPONENTS Interpreter Development.Module REQUIRED)
 include(FetchContent)
 FetchContent_Declare(nanobind GIT_REPOSITORY https://github.com/wjakob/nanobind.git GIT_TAG v1.4.0)
 FetchContent_MakeAvailable(nanobind)